Adhesive binders for layered alumopolymer composite materials

Results of studies of rheological and physico-mechanical properties of adhesive binders as components of adhesive prepregs based on glass fillers are presented. It was shown that VSK-14mR adhesive binder, which has low dynamic viscosity and high deformation and thermal strength characteristics, provides adhesive prepregs based on glass fiber rovings for layered alumopolymer composite materials.     

A study of the rheological properties of adhesive binders

Rheological properties of the VSK-14-2MR, VSK-14-3, and VSK-14-5M are studied depending on the temperature–time parameters of the technology for the production of glued prepregs. The temperature range of the processing of the binders of the given brands is determined, which allows the production of the glued prepreg with the optimal degree of properties.     

On the possibility of using of materials based on adhesive prepregs in Arctic conditions

Analysis of the properties of adhesive prepregs, which were synthesized based on glass fabrics and carbon fillers, and materials made on their basis was performed. It was shown that the composite materials based on prepregs with VSK-14-2m binder surpass composite materials based on prepregs synthesized by the impregnation of fabrics with soluble binders in terms of physical and mechanical properties at–130°C, water resistance, hygroscopicity, and water absorption.     

Adhesive-Strength Evaluation via the <Emphasis Type="Italic">Pull-Out</Emphasis> Method in a Binder—Elementary-Filament System at Various Treatments of Filaments

The adhesive strength of binders with elementary filaments that have been used for the production of LUP carbon tape covered by different types of coatings is evaluated via the pull-out method. Two types of single-layer coatings are considered, one of which is based on titanium of the VT1-0 brand while the other is made of 12Kh18N10T steel, as well as a bilayer coating composed of a titanium layer coated by a stainlesssteel layer. The adhesive strength is determined for thermoreactive (epoxy with amine hardener) and thermoplastic (polyamide) types of binders. The best adhesive strength (more than 30%) of binders is achieved when the LUP carbon tape is covered with stainless steel.     

Epoxy and polyurethane adhesive materials of elad,aquapol, and acrolat brands and their components

Different groups of chemical products developed and produced at the Macromer Scientific and Manufacturing Company are described and recommended for use in adhesive compositions, including reactive diluents for epoxy compositions, urethane prepolymers, binders for photocurable materials, aqueous polyurethane dispersions. The main characteristics of binders for glues are presented, as well as the prospects for their application in formulas of adhesive compositions.     

Heat- and high-temperature-resistant adhesives for joining carbon and ceramic materials

A review of the literature datas on the application of adhesives based on inorganic binders for joining carbon and ceramic materials was presented and their advantages and disadvantages were revealed. It was concluded that the most preferable for many application fields are polymer carbonizing adhesives with special fillers, and the most promising are the cold-setting adhesives. Datas are presented on the development of new modified ZhTK-14D adhesive compositions that are efficient at temperatures up to 1800°C intended for joining carbon and ceramic materials.     

Investigation of rheological properties of modified carbamide-formaldehyde oligomers

Comparative results of determining the rheological properties of modified adhesive compositions based on carbamide-formaldehyde binders, main wood species, and flax shive are presented.     

HIV-1 protease inhibitors from inverse design in the substrate envelope exhibit subnanomolar binding to drug-resistant variants

The acquisition of drug-resistant mutations by infectious pathogens remains a pressing health concern, and the development of strategies to combat this threat is a priority. Here we have applied a general strategy, inverse design using the substrate envelope, to develop inhibitors of HIV-1 protease. Structure-based computation was used to design inhibitors predicted to stay within a consensus substrate volume in the binding site. Two rounds of design, synthesis, experimental testing, and structural analysis were carried out, resulting in a total of 51 compounds. Improvements in design methodology led to a roughly 1000-fold affinity enhancement to a wild-type protease for the best binders, from a Ki of 30-50 nM in round one to below 100 pM in round two. Crystal structures of a subset of complexes revealed a binding mode similar to each design that respected the substrate envelope in nearly all cases. All four best binders from round one exhibited broad specificity against a clinically relevant panel of drug-resistant HIV-1 protease variants, losing no more than 6-13-fold affinity relative to wild type. Testing a subset of second-round compounds against the panel of resistant variants revealed three classes of inhibitors: robust binders (maximum affinity loss of 14-16-fold), moderate binders (35-80-fold), and susceptible binders (greater than 100-fold). Although for especially high-affinity inhibitors additional factors may also be important, overall, these results suggest that designing inhibitors using the substrate envelope may be a useful strategy in the development of therapeutics with low susceptibility to resistance.     

Covalent flexible peptide docking in Rosetta

Electrophilic peptides that form an irreversible covalent bond with their target have great potential for binding targets that have been previously considered undruggable. However, the discovery of such peptides remains a challenge. Here, we present Rosetta CovPepDock, a computational pipeline for peptide docking that incorporates covalent binding between the peptide and a receptor cysteine. We applied CovPepDock retrospectively to a dataset of 115 disulfide-bound peptides and a dataset of 54 electrophilic peptides. It produced a top-five scoring, near-native model, in 89% and 100% of the cases when docking from the native conformation, and 20% and 90% when docking from an extended peptide conformation, respectively. In addition, we developed a protocol for designing electrophilic peptide binders based on known non-covalent binders or protein–protein interfaces. We identified 7154 peptide candidates in the PDB for application of this protocol. As a proof-of-concept we validated the protocol on the non-covalent complex of 14-3-3σ and YAP1 phosphopeptide. The protocol identified seven highly potent and selective irreversible peptide binders. The predicted binding mode of one of the peptides was validated using X-ray crystallography. This case-study demonstrates the utility and impact of CovPepDock. It suggests that many new electrophilic peptide binders can be rapidly discovered, with significant potential as therapeutic molecules and chemical probes.

We developed Rosetta CovPepDock, a computational pipeline for covalent peptide docking. We showed it is highly accurate in retrospective benchmarks, and applied it prospectively to design potent and selective covalent binders of 14-3-3σ.     

Influence of energy characteristics of the fiber-binder interface on polymer composite strength

A correlation between the energy characteristics of fiber-binder interfaces and tensile strength of polymer composite materials (PCMs) was demonstrated by the example of microplastics based on carbon fiber. A new approach for express prediction of the strength properties of PDMs based on determination of the adhesive characteristics of polymer binders in model systems by the wetting method was proposed and experimentally confirmed.     

Oligomer epoxy binders with controllable molecular characteristics: Curing rheokinetics

A method for calculation of molecular characteristics and compositions of the mixtures of industrial epoxy diane oligomers (EDOs) with the given parameters of molecular weights and molecular weight distribution is proposed. Using the rheokinetic investigation techniques, the time ranges of the initial stages of EDO curing were defined and the dependence of time parameters of curing on the molecular characteristics and fractional compositions of the mixtures of these oligomers were determined. The investigations performed allow calculation, prediction, and optimization of compositions of epoxy binders and technological parameters of different stages of the production of polymer-composite materials and adhesive bonds with a complex of given properties.     

Organic and inorganic binder-coating properties for immobilization of photocatalytic ZnO nanopowders

Research on Chemical Intermediates - Five kinds of organic binders, three kinds of inorganic binders, and four kinds of organic–inorganic double-layer binders were prepared to immobilize...     

Current-conducting adhesives developed at OAO Kompozit

Requirements for current-conducting adhesives used to assemble electric and radio products are formulated. Current-conducting adhesives presently used in Russian and foreign practice are reviewed. The main characteristics of current-conducting, hot-cured TZK-14s adhesive developed at OAO Kompozit are given. Based on preliminary testing, TZK-14s adhesive has been proposed as a substitute for VK-20 adhesive (which contains silver powder), the components of which are no longer produced in Russia.     

Phenol-Derived Carbon Sealant Inspired by a Coalification Process

Recently, emerging functions utilizing phenolic molecules, such as surface functionalizing agents or bioadhesives, have attracted significant interest. However, the most important role of phenolic compounds is to produce carbonized plant matter called “coal”, which is widely used as an energy source in nearly all countries. Coalification is a long-term, high-temperature process in which phenols are converted into conducting carbonized matter. This study focuses on mimicking coalification processes to create conducting sealants from non-conducting phenolic compounds by heat treatment. We demonstrate that a phenolic adhesive, tri-hydroxybenzene (known as pyrogallol), and polyethylenimine mixture initially acts as an adhesive sealant that can be converted to a conducting carbon sealing material. The conductivity of the phenolic sealant is about 850 Ω⁻¹ cm⁻¹, which is an approximately two-fold enhancement of the performance of carbon matter. Applications of the biomimetic adhesives described herein include conducting defect sealants in carbon nanomaterials and conducting binders for metal/carbon or ceramic/carbon composites.     

Different binders in FCC catalyst preparation: impact on catalytic performance in VGO cracking

Research on Chemical Intermediates - In the present study, four different binders including two synthesized alumina-silica sol and two commercially available binders comprising LUDOX AS-30...     

Effects of accelerated carbonation on properties of ceramic-based geopolymers

Journal of Thermal Analysis and Calorimetry - Geopolymers are considered as environmentally friendly binders with a high potential not only to lower the prices of binders, but mainly to decrease...     

Phenol‐Derived Carbon Sealant Inspired by a Coalification Process

Recently, emerging functions utilizing phenolic molecules, such as surface functionalizing agents or bioadhesives, have attracted significant interest. However, the most important role of phenolic compounds is to produce carbonized plant matter called “coal”, which is widely used as an energy source in nearly all countries. Coalification is a long‐term, high‐temperature process in which phenols are converted into conducting carbonized matter. This study focuses on mimicking coalification processes to create conducting sealants from non‐conducting phenolic compounds by heat treatment. We demonstrate that a phenolic adhesive, tri‐hydroxybenzene (known as pyrogallol), and polyethylenimine mixture initially acts as an adhesive sealant that can be converted to a conducting carbon sealing material. The conductivity of the phenolic sealant is about 850 Ω^?1 cm^?1, which is an approximately two‐fold enhancement of the performance of carbon matter. Applications of the biomimetic adhesives described herein include conducting defect sealants in carbon nanomaterials and conducting binders for metal/carbon or ceramic/carbon composites.     

Application of the Kohonen artificial neural network in the identification of proteinaceous binders in samples of panel painting using gas chromatography-mass spectrometry

Historically, three types of proteinaceous matter--casein, egg and animal glue--were used as binders for pigments or as adhesives in easel and wall painting. The relative percentage content of alanine, glycine, valine, leucine, isoleucine, serine, tyrosine, phenylalanine, aspartic acid, glutamic acid, lysine, methionine, proline and hydroxyproline, as determined by GC-MS, is used for binder identification. In this paper we analyse the viability of a multivariate modelling using Kohonen's neural network to characterise the wood adhesive in 16 old samples from Italian panel paintings of the 12-16th centuries. As a training set we use the amino acid composition of 141 samples contributed by the Opificio delle Pietre Dure of Florence (Cultural Heritage Ministry, Italy). Of the 141 samples, 113 were used to train the Kohonen neural network and the remaining 28 as the evaluation set. A specificity and sensitivity of 100% was achieved in training and 92-100% in prediction depending on the assignation criteria employed. The neural network thus trained and evaluated was applied to the old samples, achieving identification of all of them. In addition, the map obtained for each amino acid provides relevant information as to its importance in the characterisation of the sample.     

Polyurethane/Dermatan Sulfate Copolymers as Hemocompatible,Non‐Biofouling Materials

The range of application of polyurethanes has been limited by their poor hemocompatibility and inability to resist non‐specific binding of biomolecules and cells. In this work, a non‐adhesive PU‐based material was synthesized via the copolymerization of PU with dermatan sulfate. Incorporation of DS into the PU backbone dramatically increased material hydrophilicity and decreased protein adsorption. The in vitro adhesion of several cell types, including platelets, also significantly decreased with increasing DS content. Both the physical and biological properties of the DS contributed to the anti‐adhesive properties of the PU/DS copolymer, and this anti‐adhesive nature of PU/DS renders this new biomaterial attractive for blood‐contacting or non‐fouling applications.